When pins of an IC (Integrated Circuit) are soldered to wires formed on a wiring board called a printed board, it has been important to prevent the occurrence of the positional misalignment.
An example of a technique for preventing the occurrence of the positional misalignment is known from patent literature 1. Patent Literature 1 discloses a printed wiring board and a printed wiring circuit board to achieve “an object of improving the yield and reliability in reflow-soldering to the printed wiring board the surface-mounted component differing in number of the electrodes between the right and left sides of the component. For the disclosed board, a pad 12(1) on the side having the small number of electrodes is lengthened in the same direction as this small-number-of-electrode side of the component. This allows the lead electrode 22(1) on the small-number-of-electrode side to be soldered at the sufficient soldering surface to the corresponding lengthened pad 12(1a) of the printed wiring board 10.